\section{Related work}
\label{related-work}
% Surveys? Papers? Rename section?
We were only able to present a small amount of existing ontology editors in this paper. In 2004 Michael Denny \cite{tools_survey} summarized important features of most common programs. He provides a comprehensive overview\footnote{\url{http://www.xml.com/2004/07/14/examples/Ontology_Editor_Survey_2004_Table_-_Michael_Denny.pdf}} and gives guidelines on how to choose the right solution. Denny performed his survey in 2002 and 2004. The big problem is that many things have changed since 2004, thus the presented results are not relevant for this paper.

Another important point in ontology engineering is the evolution of ontologies. In \cite{ontology_evolution}, L. Stojanovic et. al. discuss the requirements ontology editors have to fulfill in order to support ontology evolution. The discussed tools Prot\'{e}g\'{e}, OntoEdit and OilEd did not perform well in the evaluation. Those findings indicate that there is still much space for improvement of existing editors.

Another interesting approach of automatic generation of ontology editors has been presented in \cite{auto_ontology_generation}. The paper deals with an introduction to the usage of Prot\'{e}g\'{e}-II and Prot\'{e}g\'{e} 2000 in order to build custom-tailored ontology editors. This is a prime example of how far research regarding ontology editors goes.